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The supersymmetric prediction for the muon transverse polarization in the $K^+ \leftarrow π^0 μ^+ ν_μ$ decay

Marco Fabbrichesi·Francesco Vissani
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Abstract

The muon transverse polarization in the $K^+ \leftarrow π^0 μ^+ ν_μ$ decay will be measured at the $10^{-4}$ level in forthcoming experiments. We compare the phenomenological perspectives with the theoretical predictions in supersymmetric extensions of the standard model. In the minimal extension, CP-violating phases lead to a non-zero transverse polarization, that however is too small to account for a positive experimental signal. The problems that one encounters when departing from minimal assumptions are discussed. An observable effect is possible if the hypothesis of R-parity conservation is relaxed, but only at the price of assuming a very special pattern for the R-parity breaking couplings.

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Marco Fabbrichesi, Francesco Vissani. 1996-11-05. The supersymmetric prediction for the muon transverse polarization in the $K^+ \leftarrow π^0 μ^+ ν_μ$ decay. https://doi.org/10.1103/physrevd.55.5334

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